Low suspension arm strut coupling

ABSTRACT

A low suspension arm strut coupling is provided for a suspension of an off-road vehicle. The suspension comprises a lower suspension arm that is hingedly coupled between a chassis of the off-road vehicle and a spindle assembly that is coupled with a front wheel. An upper suspension arm is hingedly coupled between the chassis and the spindle assembly. A strut is coupled between the lower suspension arm and the chassis. A lower pivot couples the strut to the lower suspension, and an upper pivot couples the strut to the chassis. The upper and lower pivots provide a lower center of gravity of the off-road vehicle and a relatively smaller shock angle. The lower suspension arm is reinforced to withstand forces due to movement of the front wheel and operation of the strut in response to travel over terrain.

PRIORITY

This application is a Continuation of U.S. patent application Ser. No.15/625,660, filed Jun. 16, 2017, which claims the benefit of andpriority to U.S. Provisional Application No. 62/480,960, filed Apr. 1,2017, both of which are incorporated by reference in their entiretyherein.

FIELD

The field of the present disclosure generally relates to vehiclesuspension systems. More particularly, the field of the inventionrelates to an off-road front suspension system configured to improve themechanical strength and performance of off-road drivetrains.

BACKGROUND

A double wishbone suspension is a well-known independent suspensiondesign using upper and lower wishbone-shaped arms to operably couple afront wheel of a vehicle. Typically, the upper and lower wishbones orsuspension arms each has two mounting points to a chassis of the vehicleand one mounting joint at a spindle assembly or knuckle. A shockabsorber and a coil spring may be mounted onto the wishbone to controlvertical movement of the front wheel. The double wishbone suspensionfacilitates control of wheel motion throughout suspension travel,including controlling such parameters as camber angle, caster angle, toepattern, roll center height, scrub radius, scrub, and the like.

Double wishbone suspensions may be used in a wide variety of vehicles,including heavy-duty vehicles, as well as many off-road vehicles, asshown in FIG. 1. FIG. 1 shows an off-road vehicle 100 that is of a Sideby Side variety. The Side by Side is a four-wheel drive off-road vehiclethat typically seats between two and six occupants, and is sometimesreferred to as a Utility Task Vehicle (UTV), a Recreational Off-HighwayVehicle (ROV), or a Multipurpose Off-Highway Utility Vehicle (MOHUV). Inaddition to the side-by-side seating arrangement, many UTVs have seatbelts and roll-over protection, and some may have a cargo box at therear of the vehicle. A majority of UTVs come factory equipped with hardtops, windshields, and cab enclosures.

The double-wishbone suspension often is referred to as “double A-arms”,although the arms may be A-shaped, L-shaped, J-shaped, or even a singlebar linkage. In some embodiments, the upper arm may be shorter than thelower arm so as to induce negative camber as the suspension jounces(rises). Preferably, during turning of the vehicle, body roll impartspositive camber gain to the lightly loaded inside wheel, while theheavily loaded outer wheel gains negative camber.

The spindle assembly, or knuckle, is coupled between the outboard endsof the upper and lower suspension arms. In some designs, the knucklecontains a kingpin that facilitates horizontal radial movement of thewheel, and rubber or trunnion bushings for vertical hinged movement ofthe wheel. In some relatively newer designs, a ball joint may bedisposed at each outboard end to allow for vertical and radial movementof the wheel. A bearing hub, or a spindle to which wheel bearings may bemounted, may be coupled with the center of the knuckle.

Constant velocity (CV) joints allow pivoting of the suspension arms andthe spindle assembly, while a drive shaft coupled to the CV jointdelivers power to the wheels. Although CV joints are typically used infront wheel drive vehicles, off-road vehicles such as four-wheeledbuggies comprise CV joints at all wheels. Constant velocity jointstypically are protected by a rubber boot and filled with molybdenumdisulfide grease.

Given that off-road vehicles routinely travel over very rough terrain,such as mountainous regions, there is a desire to improve the mechanicalstrength and performance of off-road drivetrain and suspension systems,while at the same reducing the mechanical complexity of such systems.

SUMMARY

A low suspension arm strut coupling is provided for a suspension of anoff-road vehicle. The suspension generally couples a front wheel with achassis of the off-road vehicle and comprises an upper suspension armhingedly coupled between the chassis and a spindle assembly that iscoupled with the front wheel. A lower suspension arm is hingedly coupledbetween the chassis and the spindle assembly. A strut is coupled betweenthe lower suspension arm and the chassis. The strut is coupled betweenthe lower suspension arm and the chassis by way of a lower pivot mountedto the lower suspension arm and an upper pivot mounted to the chassis.The lower pivot and the upper pivot are configured to provide a lowercenter of gravity of the off-road vehicle and a relatively smaller shockangle. The lower suspension arm is reinforced to provide a structuralintegrity suitable to withstand forces due to movement of the frontwheel and operation of the strut in response to travel over terrain.

In an exemplary embodiment, a suspension for coupling a front wheel witha chassis of an off-road vehicle comprises an upper suspension armhingedly coupled between the chassis and a spindle assembly that iscoupled with the front wheel; a lower suspension arm hingedly coupledbetween the chassis and the spindle assembly; a strut coupled betweenthe lower suspension arm and the chassis; and a steering rod comprisinga rod-end joint coupled with a leading portion of the spindle assembly.

In another exemplary embodiment, the strut is coupled between the lowersuspension arm and the chassis by way of a lower pivot mounted to thelower suspension arm and an upper pivot mounted to the chassis. Inanother exemplary embodiment, the lower pivot and the upper pivot areconfigured to provide a lower center of gravity of the off-road vehicleand a relatively smaller shock angle. In another exemplary embodiment,the lower pivot and the upper pivot are configured to provide asubstantially 90-degree angle between the strut and the lower suspensionarm during full compression of the strut. In another exemplaryembodiment, the strut is configured to dampen vertical motion of thelower suspension arm and the upper suspension arm due to movement of thefront wheel in response to travel over terrain. In another exemplaryembodiment, the lower suspension arm is reinforced to provide astructural integrity suitable to withstand forces due to movement of thefront wheel and operation of the strut in response to travel overterrain.

In another exemplary embodiment, each of the upper suspension arm andthe lower suspension arm is comprised of two inboard mounting points tothe chassis and an outboard rod-end joint to the spindle assembly. Inanother exemplary embodiment, the inboard mounting points are comprisedof bushing joints configured to allow vertical rotation of the lower andupper suspension arms with respect to the chassis.

In another exemplary embodiment, the upper suspension arm is configuredto facilitate coupling the strut between the lower suspension arm andthe chassis. In another exemplary embodiment, the upper suspension armis coupled with the chassis forward of a coupling between the lowersuspension arm and the chassis to provided clearance for extending thestrut from the lower suspension arm to the chassis. In another exemplaryembodiment, the upper suspension arm is configured in the form of aJ-arm. In another exemplary embodiment, the upper suspension armcomprises inboard mounting joints that are coupled with the chassisforward of inboard mounting joints comprising the lower suspension arm,such that at least a rear portion of the upper suspension arm isdisposed forwardly of a portion of the lower suspension arm. In anotherexemplary embodiment, the strut is coupled with the portion of the lowersuspension arm and the chassis.

In an exemplary embodiment, a lower suspension arm for a frontsuspension of an off-road vehicle comprises one or more inboard mountingpoints to a chassis of the vehicle; an outboard mounting point to aspindle assembly coupled with a front wheel; and a pivot configured toreceive a lower end of a strut. In another exemplary embodiment, the oneor more inboard mounting points are comprised of bushing jointsconfigured to allow vertical rotation of the lower suspension arm withrespect to the chassis. In another exemplary embodiment, the outboardmounting point is configured to receive a rod-end joint coupled with thespindle assembly. In another exemplary embodiment, the outboard mountingpoint is configured to receive a weld-in tube end. In another exemplaryembodiment, the outboard mounting point is configured to receive athreaded shank comprising the rod-end joint and a lock-nut to fixate thethreaded shank with respect to the lower suspension arm.

In another exemplary embodiment, the pivot is configured to provide asubstantially 90-degree angle between the strut and the lower suspensionarm during full compression of the strut. In another exemplaryembodiment, the strut is configured to dampen vertical motion of thelower suspension arm due to movement of the front wheel in response totravel over terrain. In another exemplary embodiment, the lowersuspension arm is reinforced to provide a structural integrity suitableto withstand forces due to the movement of the front wheel and operationof the strut in response to travel over terrain.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings refer to embodiments of the present disclosure in which:

FIG. 1 illustrates an exemplary embodiment of an off-road vehicle thatis particularly suitable for implementation of an off-road frontsuspension system in accordance with the present disclosure;

FIG. 2 illustrates a front view of a front suspension system that isconfigured to couple a front wheel with a passenger side of an off-roadvehicle;

FIG. 3 illustrates a front view of an exemplary embodiment of outboardrod-end joints coupling a spindle assembly with upper and lowersuspension arms;

FIG. 3A illustrates a lower isometric view of an exemplary embodiment ofa low suspension arm strut coupling that may be incorporated into thefront suspension of the off-road vehicle;

FIG. 3B illustrates a front plan view of the low suspension arm strutcoupling of FIG. 3A;

FIG. 4A illustrates a front plan view of an exemplary embodiment ofrod-end joint coupling a spindle assembly with a suspension arm;

FIG. 4B illustrates a side plan view of the rod-end joint of FIG. 4A;and

FIG. 5 illustrates a perspective view of an exemplary embodiment ofrod-end joint that includes a lubricating race and a lubricationfitting.

While the present disclosure is subject to various modifications andalternative forms, specific embodiments thereof have been shown by wayof example in the drawings and will herein be described in detail. Theinvention should be understood to not be limited to the particular formsdisclosed, but on the contrary, the intention is to cover allmodifications, equivalents, and alternatives falling within the spiritand scope of the present disclosure.

DETAILED DESCRIPTION

In the following description, numerous specific details are set forth inorder to provide a thorough understanding of the present disclosure. Itwill be apparent, however, to one of ordinary skill in the art that theinvention disclosed herein may be practiced without these specificdetails. In other instances, specific numeric references such as “firstjoint,” may be made. However, the specific numeric reference should notbe interpreted as a literal sequential order but rather interpreted thatthe “first joint” is different than a “second joint.” Thus, the specificdetails set forth are merely exemplary. The specific details may bevaried from and still be contemplated to be within the spirit and scopeof the present disclosure. The term “coupled” is defined as meaningconnected either directly to the component or indirectly to thecomponent through another component. Further, as used herein, the terms“about,” “approximately,” or “substantially” for any numerical values orranges indicate a suitable dimensional tolerance that allows the part orcollection of components to function for its intended purpose asdescribed herein.

In general, the present disclosure describes a suspension for coupling afront wheel with a chassis of an off-road vehicle. The suspensioncomprises an upper suspension arm that includes two inboard mountingpoints to the chassis and one outboard rod-end joint to a spindleassembly coupled with the front wheel. A lower suspension arm comprisestwo inboard mounting points to the chassis and one outboard rod-endjoint to the spindle assembly. Each outboard rod-end joint is comprisedof a ball that is rotatable within a casing that is threadably coupledwith each of the upper and lower suspension arms. A bolt fastens each ofthe balls between a pair of parallel prongs extending from the spindleassembly, such that the upper and lower suspension arms may pivot withrespect to the spindle assembly during vertical motion of the spindleassembly, as well as during horizontal rotation of the spindle assemblydue to steering. A strut comprising a shock absorber and a coil springis coupled between the lower suspension arm and the chassis. The uppersuspension arm is configured to facilitate coupling the strut betweenthe lower suspension arm and the chassis. A steering rod is coupled withthe spindle assembly by way of a steering rod-end joint that is disposedat a front of the spindle assembly. The steering rod-end joint iscomprised of a ball that is rotatable within a casing that is threadablycoupled with the steering rod. A pair of parallel prongs and a bolthingedly couple the steering rod-end with the spindle assembly, suchthat the steering rod-end joint allows vertical and horizontalrotational motion of the spindle assembly during operation of theoff-road vehicle. The steering rod-end joint is coupled with the spindleassembly forward of a drive axle, thereby decreasing leverage of thefront wheel on the steering rod and substantially eliminating bump steerthat may occur due to rough terrain.

FIG. 1 shows an off-road vehicle 100 that is particularly suitable forimplementation of an off-road front suspension system in accordance withthe present disclosure. As disclosed hereinabove, the off-road vehicle100 generally is of a Utility Task Vehicle (UTV) variety that seats twooccupants, includes a roll-over protection system 104, and may have acab enclosure 108. Rear wheels 112 of the off-road vehicle 100 may beoperably coupled with a chassis 116 by way of a trailing arm suspensionsystem. Front wheels 120 may be operably coupled with the chassis 116 byway of the front suspension system disclosed herein. It should beunderstood, however, that the front suspension system of the presentdisclosure is not to be limited to the off-road vehicle 100, but ratherthe front suspension system may be incorporated into a wide variety ofoff-road vehicles, other than UTVs, without limitation.

FIG. 2 illustrates a front view of a front suspension system 124 that isconfigured to couple the front wheel 120 with a passenger side of theoff-road vehicle 100. The front suspension system 124 is comprised of anupper suspension arm 128 and a lower suspension arm 132 that couple thefront wheel 120 with the chassis 116. Each of the upper and lowersuspension arms 128, 132 comprises two inboard mounting points 136 tothe chassis 116 and one outboard mounting joint to a spindle assembly140. As will be recognized, the upper and lower suspension arms 128, 132generally are of a double wishbone variety of suspension thatfacilitates controlling various parameters affecting the orientation ofthe wheel 120 with respect to the off-road vehicle 100, such as, by wayof non-limiting example, camber angle, caster angle, toe pattern, rollcenter height, scrub radius, and scuff.

It should be understood that although the front suspension system 124 isdisclosed specifically in connection with the passenger side of theoff-road vehicle 100, a driver side front suspension system is to becoupled with a driver side of the off-road vehicle. It should be furtherunderstood that the driver side front suspension system is substantiallyidentical to the front suspension system 124, with the exception thatthe driver side front suspension system is configured specifically tooperate with the driver side of the off-road vehicle 100. As will beappreciated, therefore, the driver side front suspension system and thefront suspension system 124 may be configured as reflections of oneanother across a longitudinal midline of the off-road vehicle 100.

As shown in FIG. 2, a strut 144 that is comprised of a shock absorberand a coil spring is mounted to the lower suspension arm 132 by way of alower pivot 148. An upper pivot (not shown) couples a top of the strut144 to the chassis 116. The strut 144 is configured to control verticalmotion of the front suspension system 124 due to movement of the frontwheel 120 as the off-road vehicle 100 travels over bumpy terrain. Theupper suspension arm 128 may be suitably configured, such as in the formof a J-arm, so as to facilitate coupling the strut 144 between the lowersuspension arm 132 and the chassis 116 in lieu of being coupled betweenthe upper suspension arm and the chassis.

In some embodiments, coupling the strut 144 with the lower suspensionarm 132 positions the strut at between 8 inches and 10 inches lower,with respect to the chassis 116, than the position of the strut whencoupled with the upper suspension arm 128. Experimental observation hasshown that the lower position of the strut 144 generally facilitates alower center of gravity of the off-road vehicle 100 and a relativelysmaller shock angle, as well as eliminating a need for extending thestrut towers through and above a hood of the off-road vehicle 100. Inone embodiment, the coupling of the strut 144 with the lower suspensionarm 132 positions the strut at substantially 90-degrees with respect tothe lower pivot 148 and the upper pivot during full compression of thestrut.

As shown in FIG. 2, a drive axle 146 is coupled between a transaxle andthe front wheel 120. The drive axle 146 is configured to conduct torquefrom the transaxle to the front wheel 120 and accommodate verticalpivoting motion of the front suspension assembly 124 in response to roadconditions. As best shown in FIG. 3, the drive axle 146 is comprised ofa constant velocity (CV) joint 152 that is coupled with the spindleassembly 140 onto which the front wheel is mounted. The CV joint 152allows uninterrupted torque transmission from the transaxle to the frontwheel 120 during vertical pivoting of the front suspension assembly 124due to road conditions. As will be appreciated, the spindle assembly 140generally supports the CV joint 152 and the front wheel 120 by way ofone or more roller bearings (not shown).

As further shown in FIG. 3, the spindle assembly 140 is pivotallycoupled with the upper and lower suspension arms 128, 132. An upperrod-end joint 156 couples the upper suspension arm 128 to the spindleassembly 140, and a lower rod-end joint 160 couples the lower suspensionarm 132 to the spindle assembly. Preferably, the upper and lower rod-endjoints 156, 160 are of a Heim-joint variety, wherein each of the jointsis comprised of a ball 164 that is movable within a casing 168 that isthreadably coupled with each of the suspension arms 128, 132. A bolt 172fastens each of the balls 164 between a pair of parallel prongs 176extending from the spindle assembly 140. It is contemplated that arecess 180 disposed between each pair of parallel prongs 176 has a shapeand a size that are suitable to fixedly receive the ball 164 and allowfor a desired degree of movement of the casing 168 on the ball. Thus,during vertical motion of the spindle assembly 140, as well as duringhorizontal rotation of the spindle assembly 140 due to steering, theballs 164 rotate within their respective casings 168, allowing the upperand lower suspension arms 128, 132 to pivot with respect to the spindleassembly 140.

Upon inspection of FIG. 3, it will be recognized that the upper andlower rod-end joints 156, 160 are similar to Clevis fasteners. Forexample, each pair of parallel prongs 176 is similar to a Clevis, thebolt 172 is similar to a Clevis pin, and the ball 164 and casing 168 aresimilar to a tang. As such, each of the upper and lower rod-end points156, 160 provides two shear planes that may withstand twice the incidentforce that may be withstood by single shear joints that are used inconventional front suspensions.

In the embodiment illustrated in FIG. 3, a steering rod 184 couples thespindle assembly 140 with a steering system of the off-road vehicle 100.The steering rod 184 is coupled with the spindle assembly 140 by way ofa rod-end joint 188 that is similar to the upper and lower rod-endjoints 156, 160. It is contemplated, therefore, that the rod-end joint188 may be of the Heim-joint variety or may be of a bushing variety, asdesired. A pair of parallel prongs 192 and a bolt 196 hingedly couplethe steering rod 184 with the spindle assembly 140. As will beappreciated, the rod-end joint 188 allows vertical and horizontalrotational motion of the spindle assembly 140 during operation of theoff-road vehicle 100.

In the embodiment illustrated in FIG. 3, the rod-end joint 188 iscoupled with the spindle assembly 140 forward of the drive axle 146,thereby providing a leading-edge steering system to the off-road vehicle100. Experimentation has demonstrated that the leading-edge steeringsystem shown in FIG. 3 advantageously decreases leverage of the frontwheel 120 on the rod-end joint 188 and the steering rod 184, therebysubstantially eliminating bump steer that may occur due to forcesexerted on the front wheel by rough terrain.

FIGS. 3A-3B illustrate an exemplary embodiment of a leading-edgesteering system 240 that is advantageously incorporated into the frontsuspension of the off-road vehicle 100. Similar to the embodimentillustrated in FIG. 3, the leading-edge steering system 240 is comprisedof a steering rod 184 that is coupled with the spindle assembly 140 byway of a rod-end joint 188 that is disposed forward of the drive axle146. As disclosed above, the rod-end joint 188 may be of the Heim-jointvariety or may be of a bushing variety, such that the rod-end joint 188allows vertical and horizontal rotational motion of the spindle assembly140. Opposite of the rod-end joint 188, the steering rod 184 is coupledwith a steering gear 244 that is mounted onto a central location of thechassis 116. During operating the off-road vehicle, turning the steeringgear 244 clockwise moves the steering rod 184 toward the spindleassembly 140, causing the front wheel 120 to turn rightward. Turning thesteering gear 244 moves the steering rod 184 away from the spindleassembly 140, thereby turning the front wheel 120 leftward.

During traveling over rough terrain, the steering rods 184 comprisingthe leading-edge steering system 240 are exposed primarily to tensileforces, unlike tie-rods comprising conventional trailing-edge steeringsystems that endure primarily compression forces. It will be recognizedby those skilled in the art that although the yield strength of steelgenerally is independent of tension and compression, the steering rod184 generally may support a greater load in tension than in compression.As will be appreciated, a tensile force requires all sections of thesteering rod 184 to yield before failure of the steering rod may occur,whereas in the case of a compression force, failure of the steering rod184 due to buckling generally requires a relatively lower force actingat a weakest section of the rod. Under the action of the compressionforce, therefore, failure of the steering rod 184 may occur when any onesection of the steel fails rather than requiring all sections to fail asoccurs with tensile forces. As such, the leading-edge steering system240 is capable of withstanding relatively much greater forces due torough terrain than may be tolerated by conventional, trailing-edgesteering systems.

In the embodiment illustrated in FIGS. 3A-3B, the upper and lowersuspension arms 128, 132 are configured for coupling the strut 144 withthe lower suspension arm 132, as discussed with respect to FIG. 2. Asbest shown in FIG. 3B, the lower suspension arm 132 comprises a lowerpivot 148 that is configured to receive a lower end of the strut 144. Anupper pivot 248, shown in FIG. 3A, is suitably disposed on the chassis116 and configured to receive an upper end of the strut 144, such thatthe strut may dampen vertical motion of the upper and lower suspensionarms 128, 132 with respect to the chassis 116. Two inboard mountingjoints 136 hingedly couple the lower suspension arm 132 with the chassis116. Similarly, the upper suspension arm 128 is coupled with the chassis116 by way of two inboard mounting joints 252. The inboard mountingjoints 136, 252 generally are of a bushing or rod-end variety and allowvertical rotation of the lower and upper suspension arms 132, 128 withrespect to the chassis 116. Further, in some embodiments, the lowersuspension arm 132 may be reinforced so as to possess a structuralintegrity suitable to withstand forces due to strut 144 and the movementof the front wheel 120 as the off-road vehicle 100 travels over bumpyterrain.

As shown in FIG. 3A, the inboard mounting joints 252 are coupled withthe chassis 116 forward of the inboard mounting joints 136, therebypositioning at least a portion of the upper suspension arm 128 forwardof the lower suspension arm 132. The forward disposition of the uppersuspension arm 128 provides clearance for the strut 144 extending fromthe lower suspension arm 132 to the chassis 116. As disclosedhereinabove, coupling the strut 144 with the lower suspension arm 132positions the strut between 8 inches and 10 inches lower than theposition of the strut when coupled with the upper suspension arm 128.Experimentation has demonstrated that coupling the strut 144 with thelower suspension arm 132 generally establishes a lower center of gravityof the off-road vehicle 100 and a relatively smaller shock angle, aswell as eliminating a need for extending the strut towers above the hoodof the off-road vehicle 100. Further, in one embodiment coupling thestrut 144 with the lower suspension arm 132 provides a substantially90-degree angle between the strut 144 and the lower suspension arm 132during full compression of the strut.

FIGS. 4A-4B illustrate an exemplary embodiment of a rod-end 200 that maybe pivotally coupled with either of the upper and lower suspension arms128, 132 of the spindle assembly 140, as described herein. Like therod-end joints 156, 160, the rod-end 200 is generally of the Heim-jointvariety. The rod-end 200 is comprised of a ball 204 that is retainedwithin a casing 208, such that the ball 204 may be rotated within thecasing 208. A threaded shank 212, or a weld-in tube end, is fixedlycoupled with the casing 208 so as to enable coupling the rod-end to oneof the suspension arms 128, 132. The threaded shank 212 may be fixedlycoupled with the suspension arm by way of a lock-nut 214 (see FIG. 5)that may be threaded onto the shank 212 and rotated into forciblecontact with the suspension arm. It is contemplated that the threadedshank 212 may be configured with left-hand threads or right-handthreads, without limitation.

A bore 216 extends through the ball 204 and is configured to receive thebolt 172. The bore 216 and the bolt 172 facilitate mounting the rod-end200 to the spindle assembly 140. In particular, the bolt 172 may bepassed through suitable threaded holes in the prongs 176 and through thebore 216 so as to fixate the ball 204 in the recess 180. With the ball204 fixated between the parallel prongs 176, the casing 208 and thesuspension arm to which the rod-end 200 is fastened may be freely movedwith respect to the spindle assembly 140.

As best shown in FIG. 4B, a misalignment spacer 220 may be disposed oneach of opposite sides of the ball 204. The misalignment spacers 220ensure that the ball 204 remains centered within the recess 180, betweenthe parallel prongs 176, while providing a relatively high degree ofclearance for rotation of the casing 208 on the ball 204. In someembodiments, the misalignment spacers 220 may be threaded orpress-fitted into suitable countersunk holes in the ball 204. In someembodiments, the ball 204 and the misalignment spacers 220 may bemachined as a single component comprising an extended ball that may beinstalled into the casing 208 during manufacturing of the rod-end 200.

In some embodiments, a lubricating race may be incorporated into therod-end as to ensure sufficient lubrication is available to the ball andcasing during operation of the rod-end. For example, in an exemplaryembodiment of a rod-end 224, illustrated in FIG. 5, a lubricating race228 is disposed between the ball 204 and an interior of the casing 208.In some embodiments, the lubricating race 228 may be comprised of aheavy duty, injection molded Teflon impregnated Nylon race that isconfigured to ensure smooth and precise movement of the ball 204 withinthe casing 208. In some embodiments, the lubricating race 228 may becomprised of a thin chamber between the ball 204 and an interior of thecasing 208. A suitable lubricant, such as a high-quality grease, may bedisposed within the thin chamber so as to lubricate movement between theball 204 and the casing 208. A lubrication fitting 232 may be disposedin the casing 208 and in fluid communication with the thin camber tofacilitate periodic replenishment of the lubricant within the thinchamber.

In some embodiments, the rod-ends 200, 224 may be configured to haveself-lubricating properties. For example, in some embodiments, the ballsand casings 204, 208 may be comprised of stainless steel that is treatedwith polytetrafluoroethylene (PTFE). It is contemplated that any ofvarious PTFE-based formulations may be applied to the rod-ends 200, 224,without limitation. In some embodiments, PTFE-treated stainless steelballs and casings 204, 208 may be coupled with a lubricating race 228that is comprised of an injection molded Teflon impregnated Nylon race,without limitation.

It is contemplated that the rod-ends 200, 224 may be treated duringmanufacturing so as to optimize hardness, strength, durability, andlongevity. In some embodiments, the casings 208 may be machined 4130chromoly, and the balls 204 may be comprised of 52100 bearing steel. Theballs and casings 204, 208 may be heat-treated and hard-chrome finishedso as to improve strength and corrosion resistance. Further, the ballsand casings 204, 208, as well as the race 228, may be cryogenicallytreated to improve hardness, durability, and wear resistance.

While the invention has been described in terms of particular variationsand illustrative figures, those of ordinary skill in the art willrecognize that the invention is not limited to the variations or figuresdescribed. In addition, where methods and steps described above indicatecertain events occurring in certain order, those of ordinary skill inthe art will recognize that the ordering of certain steps may bemodified and that such modifications are in accordance with thevariations of the invention. Additionally, certain of the steps may beperformed concurrently in a parallel process when possible, as well asperformed sequentially as described above. To the extent there arevariations of the invention, which are within the spirit of thedisclosure or equivalent to the inventions found in the claims, it isthe intent that this patent will cover those variations as well.Therefore, the present disclosure is to be understood as not limited bythe specific embodiments described herein, but only by scope of theappended claims.

What is claimed is:
 1. A suspension for coupling a front wheel with achassis of an off-road vehicle, comprising: an upper suspension armhingedly coupled between the chassis and a spindle assembly that iscoupled with the front wheel; a lower suspension arm hingedly coupledbetween the chassis and the spindle assembly; a strut coupled betweenthe lower suspension arm and the chassis; and a steering rod comprisinga rod-end joint coupled with a leading portion of the spindle assembly.2. The suspension of claim 1, wherein the strut is coupled between thelower suspension arm and the chassis by way of a lower pivot mounted tothe lower suspension arm and an upper pivot mounted to the chassis. 3.The suspension of claim 2, wherein the lower pivot and the upper pivotare configured to provide a lower center of gravity of the off-roadvehicle and a relatively smaller shock angle.
 4. The suspension of claim2, wherein the lower pivot and the upper pivot are configured to providea substantially 90-degree angle between the strut and the lowersuspension arm during full compression of the strut.
 5. The suspensionof claim 2, wherein the strut is configured to dampen vertical motion ofthe lower suspension arm and the upper suspension arm due to movement ofthe front wheel in response to travel over terrain.
 6. The suspension ofclaim 5, wherein the lower suspension arm is reinforced to provide astructural integrity suitable to withstand forces due to movement of thefront wheel and operation of the strut in response to travel overterrain.
 7. The suspension of claim 1, wherein each of the uppersuspension arm and the lower suspension arm is comprised of two inboardmounting points to the chassis and an outboard rod-end joint to thespindle assembly.
 8. The suspension of claim 7, wherein the inboardmounting points are comprised of bushing joints configured to allowvertical rotation of the lower and upper suspension arms with respect tothe chassis.
 9. The suspension of claim 1, wherein the upper suspensionarm is configured to facilitate coupling the strut between the lowersuspension arm and the chassis.
 10. The suspension of claim 9, whereinthe upper suspension arm is coupled with the chassis forward of acoupling between the lower suspension arm and the chassis to providedclearance for extending the strut from the lower suspension arm to thechassis.
 11. The suspension of claim 9, wherein the upper suspension armis configured in the form of a J-arm.
 12. The suspension of claim 9,wherein the upper suspension arm comprises inboard mounting joints thatare coupled with the chassis forward of inboard mounting jointscomprising the lower suspension arm, such that at least a rear portionof the upper suspension arm is disposed forwardly of a portion of thelower suspension arm.
 13. The suspension of claim 12, wherein the strutis coupled with the portion of the lower suspension arm and the chassis.14. A lower suspension arm for a front suspension of an off-roadvehicle, comprising: one or more inboard mounting points to a chassis ofthe vehicle; an outboard mounting point to a spindle assembly coupledwith a front wheel; and a pivot configured to receive a lower end of astrut.
 15. The lower suspension arm of claim 14, wherein the one or moreinboard mounting points are comprised of bushing joints configured toallow vertical rotation of the lower suspension arm with respect to thechassis.
 16. The lower suspension arm of claim 14, wherein the outboardmounting point is configured to receive a rod-end joint coupled with thespindle assembly.
 17. The lower suspension arm of claim 16, wherein theoutboard mounting point is configured to receive a weld-in tube end. 18.The lower suspension arm of claim 16, wherein the outboard mountingpoint is configured to receive a threaded shank comprising the rod-endjoint and a lock-nut to fixate the threaded shank with respect to thelower suspension arm.
 19. The lower suspension arm of claim 14, whereinthe pivot is configured to provide a substantially 90-degree anglebetween the strut and the lower suspension arm during full compressionof the strut.
 20. The lower suspension arm of claim 14, wherein thestrut is configured to dampen vertical motion of the lower suspensionarm due to movement of the front wheel in response to travel overterrain.